On Fri, 12 Nov 2021 at 18:01, LianCheng <tanl...@gmail.com> wrote: > Hi, > > I tried to run several ffmpeg processes with different input mp4 files and > to different outputs within my PC (having Intel Core i7). The mp4 video > resolution is full HD format. > > ffmpeg -re -stream_loop -1 -i 1.mp4 -c:v libx264 -preset ultrafast -tune > zerolatency -maxrate 2M -bufsize 2M -r 20 -g 60 -an -c:a copy -f rtsp > rtsp://<ip_addr>:1935/cam-1 > ffmpeg -re -stream_loop -1 -i 2.mp4 -c:v libx264 -preset ultrafast -tune > zerolatency -maxrate 2M -bufsize 2M -r 20 -g 60 -an -c:a copy -f rtsp > rtsp://<ip_addr>:1935/cam-2 > ffmpeg -re -stream_loop -1 -i 3.mp4 -c:v libx264 -preset ultrafast -tune > zerolatency -maxrate 2M -bufsize 2M -r 20 -g 60 -an -c:a copy -f rtsp > rtsp://<ip_addr>:1935/cam-3 > : > : > ffmpeg -re -stream_loop -1 -i N.mp4 -c:v libx264 -preset ultrafast -tune > zerolatency -maxrate 2M -bufsize 2M -r 20 -g 60 -an -c:a copy -f rtsp > rtsp://<ip_addr>:1935/cam-N > > If I run 6 of the above ffmpeg processes, the CPU hits 100%. > > Are the parameters used optimized? I need to keep the CPU below 80%. > > Will having GPU (like nvidia) help to increase the number of ffmpeg > processes that can be run? > > Hello there,
You could try to reduce threads (set via threads -n, where n is lower than the number of total CPUs on your system). I'd typically recommend a thread setting of no more than 4, especially for hardware-based encoders such as Intel's QSV & VAAPI, and NVIDIA's NVENC. A GPU-based encoder wrapper (depending on the platform you're on and the implementation in use) *can* somewhat overcome that limitation, with caveats: 1. NVIDIA's NVENC consumer GPUs are limited to 2 encode sessions per GPU. This can be somewhat overcome with Keylase's patcher, see https://github.com/keylase/nvidia-patch 2. Only very specific codecs (and codec features) may be supported by the hardware-accelerated encoder wrapper in use, and as such, outpuit may not always be directly comparable to a software-based implementation. Please see FFmpeg's HWAccel wiki on the same: https://trac.ffmpeg.org/wiki/HWAccelIntro Warm regards, Dennis. _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
